Purpose: The April 2005 Guidelines for the Use of Antiretroviral Agents in HIV-Infected Adults and Adolescents recommended 9 regimens to be combined with 2 nucleoside reverse transcriptase inhibitors (NRTIs). These regimens are effective in lowering viral load but are expensive. This study aimed to determine the cost for each regimen to achieve an undetectable viral load. Method: 52 clinical trials were reviewed. The outcome measure was cost per undetectable patient, C divided by PU, where C = cost of a drug, and PU = percent of patients with undetectable viral loads. Results: For 30 weeks, cost per undetectable (< 400 copies/mL) ranged from $4,416 (efavirenz) to $23,110 (nelfinavir); for 42 weeks, the range was $5,729 (efavirenz) to $24,071 (indinavir/ritonavir); for 60 weeks, it ranged from $9,535 (efavirenz) to $26,829 (fosamprenavir); and for 84 weeks, it ranged from $12,203 (efavirenz) to $22,960 (nelfinavir). For < 50 copies/mL, at 30 weeks the range was from $7,140 (efavirenz) to $17,548 (atazanavir); for 42 weeks, it ranged from $9,849 (lopinavir/ ritonavir) to $13,181 (nelfinavir); for 60 weeks, it ranged from $8,702 (nevirapine) to $36,034 (atazanavir); and for 84 weeks, it ranged from $15,660 (efavirenz) to $29,177 (indinavir/ritonavir). Conclusion: Efavirenz's low price and high effectiveness make it the least expensive means of achieving an undetectable viral load.
